Flow within a blood vessel or other body lumen within a patient's vasculature may become constricted or ultimately interrupted for a variety of reasons. For example, a vessel may gradually narrow due to inflammation and/or cell proliferation. In addition, thrombus may form due to such narrowing or other flow problems within a vessel.
For example, an aorto-venous graft may be implanted in an arm of a patient experiencing kidney failure, e.g., to facilitate dialysis treatment. Such grafts may be a fistula formed directly in the patient's body, e.g., through tissue between an adjacent artery and vein or other vessels, may be a xenograft implanted between two vessels, or may be a synthetic graft. Such grafts only have a limited life cycle due to inflammation, thrombus formation, and the like. Once such a graft becomes sufficiently occluded or otherwise deteriorates, a new graft must be implanted at a new location for subsequent treatment.
Some medical procedures involve aspirating material from within a body lumen. Although it may be desirable to provide a relatively large aspiration lumen in a catheter or other device to facilitate aspiration, many procedures require the device to maintain a relatively small profile, e.g., to provide desired tracking performance and/or avoid damaging the passages through which the device is directed. In such devices, relatively large particles may obstruct the aspiration lumen of the device, preventing further aspiration.
Accordingly, apparatus and methods for removing material from aorto-venous grafts, blood vessels, or other body lumens would be useful.